Change get_git_commit to return full commit hash

This patch changes get_git_commit to always return the full hash.
Since different git versions do not agree on the length of the
abbreviated hash this made the length flaky. To make the length
consistent change it to always be the full hash.

src/gitcommit.cmake

@@ -13,7 +13,7 @@ if(GIT_FOUND)
 
   # Fetch the commit HASH of head (short version) using rev-parse
   execute_process(
-    COMMAND ${GIT_EXECUTABLE} rev-parse --short HEAD
+    COMMAND ${GIT_EXECUTABLE} rev-parse HEAD
     OUTPUT_VARIABLE EXT_GIT_COMMIT_HASH
     RESULT_VARIABLE _revparse_RESULT
     OUTPUT_STRIP_TRAILING_WHITESPACE)

tsl/test/shared/expected/build_info.out

@@ -4,10 +4,11 @@
 -- Check what get_git_commit returns
 SELECT pg_typeof(commit_tag) AS commit_tag_type,
        pg_typeof(commit_hash) AS commit_hash_type,
+       length(commit_hash) AS commit_hash_length,
        pg_typeof(commit_time) AS commit_time_type
   FROM _timescaledb_internal.get_git_commit();
- commit_tag_type | commit_hash_type |     commit_time_type     
------------------+------------------+--------------------------
- text            | text             | timestamp with time zone
+ commit_tag_type | commit_hash_type | commit_hash_length |     commit_time_type     
+-----------------+------------------+--------------------+--------------------------
+ text            | text             |                 40 | timestamp with time zone
 (1 row)
 

tsl/test/shared/sql/CMakeLists.txt

@@ -42,9 +42,7 @@ foreach(TEMPLATE_FILE ${TEST_TEMPLATES_SHARED})
   list(APPEND TEST_FILES_SHARED ${TEST_FILE})
 endforeach(TEMPLATE_FILE)
 
-if(DEFINED EXT_GIT_COMMIT_TAG
-   OR DEFINED EXT_GIT_COMMIT_HASH
-   OR DEFINED EXT_GIT_COMMIT_TIME)
+if(DEFINED GIT_FOUND)
   list(APPEND TEST_FILES_SHARED build_info.sql)
 endif()
 

tsl/test/shared/sql/build_info.sql

@@ -5,6 +5,7 @@
 -- Check what get_git_commit returns
 SELECT pg_typeof(commit_tag) AS commit_tag_type,
        pg_typeof(commit_hash) AS commit_hash_type,
+       length(commit_hash) AS commit_hash_length,
        pg_typeof(commit_time) AS commit_time_type
   FROM _timescaledb_internal.get_git_commit();